Possibly the best book I’ve ever read on astronomy: text and images complement each other perfectly. Even the solidness of the book was right. It’s a heavy book about heavy ideas, from the beginning of the universe to its possible endings, with everything astronomical in between.

And everything is astronomical, if it’s looked at right. The elements vital for life were cooked in stars before being blasted out by supernovae. We are star-stuff that has the unique privilege – so far as we know – of being able to understand stars.

Or trying to. This book was first published in 2012, so it’s inevitably out of date, but many of the mysteries it describes are still there. And when mysteries are solved, they sometimes create new ones. Even the behaviour and composition of a celestial body as close as the Moon is still impossible for us to explain. But sometimes it’s easier at a distance: the interior of the earth can harder to study than galaxies millions of light years away, as I pointed out in “Heart of the Mother”.

In every case, however, understanding depends on mathematics. Astronomers have been building models of the heavens with shapes and numbers for millennia, but the models had to wait for two things to really become powerful: first, the invention of the telescope; second, the development of modern chemistry and physics. Whether or not there is life out there, celestial light is full of messages about the composition and movement of the stars and other bodies that generate it.

But visible light is only a small part of the electromagnetic spectrum and modern astronomy probes the universe at wavelengths far above and below it. The more data astronomers can gather, the more they can test the mathematical models they’ve built of the heavens. The best models make the most detailed predictions, inviting their own destruction by ugly facts. But when predictions fail, it sometimes means that the observations are faulty, not the models. Cosmological models predicted much more matter in the universe than we can see. Is the gap accounted for by so-called “dark matter”, which “simply doesn’t interact with light or other electromagnetic radiations at all”? (ch. 98, “Dark Matter”, pg. 396)

Dark matter is a strange concept; so is dark energy. Astronomy may get stranger still, but the cover of this book is a reminder that human beings inhabit two kinds of universe. One is the universe out there: matter and radiation, moons, planets, stars, galaxies, supernovae. The other is the universe in here, behind the eyes, between the ears and above the tongue. The cover of this book offers a vivid contrast between the swirling complexity and colour of a star-field and the sans-serif font of the title and author’s name. But the contrast is ironic too. The stars look complex and the font looks simple, but language is actually far more complex and difficult to understand than stars.

Consciousness may be far more complex still. In the end, is the value of science that it expands consciousness, offering new physical and mental sensations of discovery and understanding? The powerful and beautiful images and ideas in this book could only have been generated by science, because the universe is more inventive than we are. But without consciousness, the universe might as well not exist. Without language, we’d never be able to try and understand it. Then again, the universe seems to have invented language and consciousness too.